Hi Frank,
You’re very welcome, I’m happy to look into any given scene files to avoid problems for others here
The Create Null or Group is the same object, only the Position is perhaps different with the “group”, hence the problems. I really advice to be careful with the short cut: Group. Really and absolutely! There, I said it twice a day. Yes, I read that it was only useable with the group, which indicates to me, something in the file is not right. However, the amount of problems you have encounter is not plausible to me. Something is missing. Sometimes a scene file can break, I advice then to start over or copy and paste things into a new fresh file.
Just as I always believe to test things is better than to write from my memory, as updates might change things: I baked a copy of an object-tracked object, while its position was not on “PSR zero’e out”, the Group short cut moved the object, not in that moment, but after moving the time-slider and back to the previous time position, the object has not the same position! A huge problem. So, please, check this carefully. I advice as much as possible against it!
Edit: Here is a little demo, the green is always the reference. The yellow and the red one are just based on the Group short cut, the blue one is based on a Null (PSR:0,0,0;1,1,1;0,0,0).
Screen capture
https://www.amazon.com/clouddrive/share/iNBcvFqNTwOCKWzAGpy7DPShxKRb9RR5pDR5KSaLy0D
/edit
I hope that sound reasonable: My target here is to work in a clean way, that means to go back where it worked and use another route if possible. After a while a scene file would be otherwise a patch-collection, perhaps hard to manage as well. Not nice. Discussing to patch an avoidable problem is not my wish.
If you have any follow up question, please let me know.
All the best